Means for treating inflammable gases



Nov. 13, 1945. J KURTH 2,389,059

MEAI IS FOR TREATING INFLAMMABLE GASES Filed June 1, 1942 2 Sheets-Sheet l KURTH Filed June 1, 1942 2 Sheets-Sheet 2 Application June 1, 1942, Serial No. 445,348

9 Claims. (6i. 181-43) This invention relates to a means for treatin inflammable gases, such as the exhaus gases of internal combustion engines and the powder gases of guns. and has for its primary object to provide a simple, practical method and means of rendering such gases noninflammable, particularly at the discharge ends of the exhaust conduits of aircrait engines and at the muzzles of guns to eliminate highly objectionable flame at these locations.

Another important object oi the invention is to provide a method and means for the primary purpose stated which serves additionaily, in connection with the exhaust conduits of internal combustion engines, to reduce the pressure in such conduits, thereby to increase the power of the engines and to promote their efliciency: also, to eliminate or at least materially reduce a primary cause or backiiring and to reduce exhaust noises by diilusing exhaust sound waves.

Another important object of the invention is to provide a means for the purposes stated embodying a construction such that, when it is associated with an inflammable gas conduit that is subjected in any manner to a flow of air therealong, as for example, in the case of aircraft-carried guns and aircraft engine exhaust conduits which are subjected to air flow therealong by operation of the aircraft propeller or due to movement of the aircraft through the atmosphere, utilizes such air flow to accomplish its purposes.

With the ioregoing and various other objects in view, which will become more iully apparent as the nature of the invention is better understood. the same consists in a method and means embodying the features of novelty as will be hereinafter more fully described, illustrated in the accompanying drawings and particularly defined in the appended claims.

In the accompanying drawings. wherein like characters of reference denote corresponding parts in related views:

Figure 1 is a longitudinal sectional view through the discharge end portion or an inflammable gas conduit and an associated conventional means for practicing the method and accomplishing the purposes of the invention.

Figure 2 is a view similar to Fig. 1 illustrating another means for practicing the method and accomplishing the purposes of the invention.

Figure 3 is another view similar to Fig. 1 illustrating another means for practicing the method and accomplishing the purposes of the invention.

Figure 4 is still another view similar to Fig. 1 illustrating still another means for practicing the method and accomplishing the purposes of the invention.

Figure 5 is a view similar to Fig. 4 illustratin as an addition to the structure shown in said fisure a venturi means for accelerating flow oi gases from the inflammable gas conduit.

Figure '8 is a view similar to Fig. 5 illustrating as an addition to the structure shown in said figure means for diflusing the diluted gases.

Figure 7 is a view similar to Fig. 1 showing a means especially adapted for use on stationary machine guns or on the rear machine guns of aircraft, for accomplishing the purposes of the invention; and

Figure 8 is a view similar to Fig. 7 showing a means especially adapted for use to accomplish the purposes of the invention when used on aircraft-carried guns or other guns that in use may be advanced through the atmosphere with their muzzles disposed forwardly.

The basic principles of the present invention are either the dilution of an inflammable gas by a noninilammable gas, sufllcient in quantity to render the inflammable gas non-inflammable; the cooling of an inflammable gas by the intermixture therewith of another gas or other medium so cold as to reduce the temperature of the inflammable gas to such a low degree as to render it noninflammable, or both the dilution and cooling of an inflammable gas by another gas or other medium so that the combined dilution and cooling render the inflammable gas non-inflammable.

The invention is particularly concerned with the treatment of inflammable gases, such as powder gases .and the exhaust gases of internal combustion engines, which flow to the atmosphere along confined paths, as for example. through gun barrels and exhaust pipes, either of which for purposes of the present description and claims may be regarded as an inflammablegas conduit, and the primary purpose of the treatment is to render such gases non-inflammable either as they flow along or as they leave the discharge end of their conduit so that any flame at the discharge end of their conduit is avoided.

Figure 1 of the drawings illustrates conventionally one manner and means of carrying the invention into practice. In said figure, i0 desighates an inflammable-gas conduit and ii designates a hollow ring or manifold disposed concentrically with respect to said conduit Iii is surrounding relationship to the discharge end portion thereof and having suitable outlet means i2 so that a gas or other fiuid medium which may be supplied to said ring in any suitable manner will ;'be delivered therefrom in the form of a surrounding or substantially surrounding stream into inflammable gases as they are discharged from said conduit Ill.

The gas or other fluid medium supplied to and delivered from the ring ii may be so relatively cold as to act solely by its cooling eifect upon the inflammable gases to suillciently reduce the temperature of the latter to render them noninflammable in the atmosphere immediately after their discharge from the conduit ill and until they have become so dissipated in the atmosphere as to be no longer inflammable, and in this way any flame at the discharge end of said conduit I II will be prevented even though the cooling gas or other cooling medium may itself be inflammable. Alternatively, the gas or other -fluid medium supplied to and delivered from.

the ring ii may be non-inflammable and of either a higher or a lower temperature than the inflammable gases discharged from the conduit l and by its dilution of the inflammable gases as they leave said conduit will serve to render said inflammable gases non-inflammable immediately after leaving said conduit and until they have become so dissipated in the atmosphere as. to be no longer inflammable, and also in this way any flame at the discharge end of the conduit ill will be prevented. Erei'erably, however, the

gas or other fluid medium supplied to and de- I livered from the ring H is both non-inflammable and of a sufllciently lower temperature than the inflammable gases issuing from the conduit in so that both diluting and cooling of the inflammable gases are factors in rendering said gases non-inflammable in the atmosphere immediately after leaving the conduit I 0 and until they have become so dissipated in the atmosphere as to avoid the possibility of any flame at the discharge end of said conduit i0.

' The invention contemplates the supply to and the delivery from the ring H of either a cooling or a diluting or a combined cooling and diluting gas or other fluid medium under a pressure suflicient to insure delivery of a required quantity of said gas or other fluid medium in a sufflciently brief period 01 time to accomplish the purpose of the invention, and in this connection it is apparent that-the outlet means l2 may be designed to direct the treating gas or other fluid medium into the inflammable gas either in a direction at right angles to the direction of flow of the inflammable gas or more or less counter to or in the same general direction as the direction of flow of the inflammable gases, whereby the treating gas or other fluid medium may be caused to intermix with and act most thoroughly and effectively upon the inflammable gases. Preferably, however, in the case of internal combustion engine exhaust gases being treated, the treating gas or other fluid mediumhas a direction of flow inwardly and more or less in the same direction as the exhaust gases to accelerate flow of the latter gases and thus reduce pressure in the exhaust conduit, both to the end of relieving back pressure on the engine and thus promoting engine eiflciency and 01' reducing back-firing which is due largely to accumulation and consequent explosion of gases in the exhaust conduit. Obviously, the ring ll may be fluid medium to the inflammable gases in the form of a surrounding or substantially surrounding stream or streams, the treating gas or other fluid medium may be delivered to the inflammable gases interiorly thereof, as for example, through a spray nozzle II located in the path of flow oi the inflammable gases as illustrated in Fig. 2 of the drawings. Obviously, the nozzle l3 or its equivalent may be located as shown within the inflammable gas conduit, designated as ill, or it may be located beyond the discharge and of said conduit, and maybe designed and arranged to discharge the treating gas or other fluid medium in any desired direction or directions relative to the direction of flow of the inflammable gases.

In cases where moves through the atmosphere or is subjected in 7 any other manner to flow of air along the outside thereof, as for example, in the case of aircraftcarried guns and aircraft engine exhaust conduits which are subjected to air flow along the outsides thereof by operation of the aircraft propeller or due to movement of the aircraft through the atmosphere, the invention contemplates utilization of the air flowing along the outside of the inflammable gas conduit as the gas for treating the inflammable gases by diluting and cooling them to accomplish the purposes of the invention, and in this connection any suitable means may be provided to direct the treating air into the inflammable gases either during flow of the inflammable gases through their conduit or as they leave their conduit to render them non-inflammable immediately after leaving their conduit, thereby to avoid flame at the discharge end of the conduit.

One means of utilizing air flowing along the outside of an inflammable-gas conduit, such as an aircraft engine exhaust conduit, in the same direction as flow of inflammable exhaust gases from the conduit is illustrated in Fig. 3 of the drawings as comprising air admission openings, designated as H, in the conduit, designated as l0, and vanes ll extending diagonally outwardly and forwardly from the rear ends of the air admission openings it so as to intercept and deflect through said openings into the conduit and into inflammable exhaust gases flowing through the latter some of the air which flows along the outside of said conduit. The openings II are suiflciently numerous or are of suflicient total area to admit the required quantity of air to the conduit, under the pressure derived from the travel of the air along the outside of the conduit, to insure sufllcient dilution and cooling of the inflammable exhaust gases to render them non-inflammable in the atmosphere when they leave the discharge end of the conduit and in this way any flame at or beyond the discharge end of the conduit is avoided. Moreover, the

diluting and cooling air has generally the same direction of flow as the inflammable exhaust gases, and if its velocity is greater than the velocity of the inflammable exhaust gases, as usual- 157 it is in the case of an aircraft engine exhaust conduit due either to the propeller slip stream when the aircraft is at rest or to both the propeller slip stream and advance of the aircraft when the latter is in flight, it serves to accelerate the flow of the exhaust gases with the advantages aforementioned in connection with the means illustrated in Fig. 1 {or carrying out the invention.

Another means of utilizing air flowing along the outside of an inflammable gas conduit in the an inflammable-gas conduit gases as they leave the discharge end oithe cona,eso,oes

same direction as flow or his gases through the conduit to accomplish the purposes oi the invention is illustrated in I'll. 4 of the drawings as comprising an open-ended, hollow, tapering member ll suitably mounted on or ad- Jacent to the discharge end portion of the ccnto the atmosphere and also to act as a shield to hide from the view of a person located rearwardly of said member any glowing gas in the duit to dilute and cool them and thus render them non-inflammable.

If desired, and as also is illustrated in m. 4'

disposed inwardly of the member it and may be spaced therefrom and from each other in case there is a plurality of them, to direct a number of streams of diluting and cooling air into inflammable gases as they leave the discharge and of the conduit it and as is apparent the members Iii, it may have different amounts of taper to direct the diflerent streams of treating air in difierent directions into the inflammable gases to most efiectively dilute and cool them.

The tapering member it, either alone or in association with one or more additional tapering members such as the tapering member or memhere it, terms, in eflect, a continuation of the conduit I 0 and therefore the means illustrated in Fig. 4 is substantially the equivalent of the means illustrated in Fig. 3 for accomplishing the purposes of the invention. In other words, the conduit alone. or the conduit in combination with the tapering member I! or the tapering members It and It, provides a confined path of flow for the inflammable gases and the treating air is delivered to the inflammable gases during their flow along said conflned path.

Air supplied through the tapering member I! or through the tapering members II, is, as the case may be, may have the samegeneral direction of flow as the inflammable gases and therefore may act to accelerate flow of such gases with the advantages aforementioned. Alternatively, the smaller end portion of any one or more of said members I! or it may be directed more or less inwardly as indicated at l! in Fig. 4 of the drawings to direct air at any desired angle into the inflammable gases. In any event, an open-ended, hollow, flaring member I8 may be joined at its smaller end to the smaller end of the tapering member l5, as illustrated in Fig. 5 of the drawings, to provide a venturi structure to accelerate flow of inflammable gases through the inflammable gas conduit, designated as "i and through the tapering member I! orthe tapering members I5 and It as the case may he. Moreover, as illustrated in Fig. 6 of the drawings, one or more smaller, open-ended, hollow flaring members It may be spaced inwardhr conduit it. On the other hand. the and pertions or the tapering and flaring members preferably overlap one another and thereby act as shields to prevent any glowing gas in the conduit W from being seen from a point at the side or and beyond the end of the conduit.

In a construction as illustrated'in Fig. 8 all of the tapering and daring members preferably have diflerent amounts or taper and flare. respectively, to break up'sound waves and thus reduce exhaust noises. However, regardless of their relative amounts of flare, said members serve eflectively tointercept sound waves and thus to reduce exhaust noises.

According to an ci'the'constructions lllustrated in Figs. 4 to 6, the tapered members and the flaring members, if used, may be connected together in a unitary structure in any desired manner. For example. struts such as illustrated at is, 20' and It" in said respectively, may be employed for that purpose and also to mount said members on a'sleeve 31 to be engaged over and fastened to the discharge end portion of an inflammable gas conduit for the purpose of mounting the unitary device thereon, as shown in Fig. 8.

In a device as illustrated in Fig. 8 the flaring member it may be provided with a small central opening a: of sumciently large diameter to permit the passage therethrough of bullets or other projectiles iired from a gun upon which the device may be mounted, and in the case of a gun that is mounted on an aircraft or other vehicle for movement through the atmosphere with its muzzle trailing, the operation of the device ,to prevent name at the muzzle of the gun will be the same as described in connection with the devices illustratedin Figs. 4 to 6. In fact, a device as illustrated in Fig. 6, may be used on stationary guns for accomplishing the purposes of the invention either by employing any suitable means for supplying air or other gas to said device for treating the powder gases issuing from the muzzle of the gun, or in'the case of rapidly flring gu such as machine guns, by utilizing the substantially continuous flow of powder gases irom the muzzle of the gun to induce flow of air through the members II, It

into the powder gases for diluting and cooling from the flaring member I8 to deflect the diluted gases outwardly and thus promote their rapid diffusion in the atmosphere. In addition, an

innermost flaring member I! closed at its smaller end preferably is provided to form the inner wall of the innermost of the flaring passageways a through which the diluted gases flow them. Preferably, however, a device constructed in accordance with the invention for use in association with either stationary machine guns or machine guns which travel through the atmosphere with their muzzles trailing embodies, as illustrated in Fig. 7 of the drawings,-a construction which fundamentally is the same as the Fig. 6 construction, except-that the tapered members, designated as l5", and the flaring members, designated as I93, are more numerous and have a more pronounced-spread apart relationship axially than the corresponding members of the Fig. 6 construction to impart greater length to the device and thereby aflord ample time within which the diluting air or gases, which are drawn between the members ll by the powder gases flowing forwardly through the device, may act to accomplish their purpose. In Fig. 7 the flaring members li l9 are shown as being connected together and to a mounting sleeve 2 I by suitable struts 20.

Figure 8 illustrates a device for use on machine guns, such as the front machine guns of aircraft, which travel through the air with their muzzles disposed forwardly. This device is generally the same as the device illustrated in Fig. 7,

except that the flaring members ll located suc-,

' bers W, W are shown as being connected to-' gather and to a mounting sleeve li by suitable struts 20.

' Prevention of flame at the muzzle or a gun or V at the discharge end of the exhaust conduit of an aircraft has the important military advantage that the location of the gun or the aircraft is not disclosed to an enemy by any such flame. In addition, fire hazards are correspondingly reduced; dilution or exhaust gases reduces the danger of monoxide poisoning, and avoidance of exhaust flame on both military and commercial aircraft has a favorable psychological effect on crew and passengers.

I claim:

1. In combination with an inflammable-gas conduit, a plurality of open-ended hollow tapering members disposed substantially in axial alinement with one another and with said conduit and located adjacent to the gas outlet end of said conduit and spaced outwardly from said conduit and from one another-and tapering in the direction of flow of gases discharged from said conduit and having successively greater amounts of taper, whereby air flowing along said conduit toward its discharge end is divided into separate streams and said streams are deflected at diflerent angles into gases dischargedfrom said conduit to dilute them.

2. In combination with an inflammable-gas conduit, an open-ended hollow tapering member disposed substantially in axial alinement with said conduit adjacent to the outlet end thereof and tapering in the direction of flow of gases discharged from said conduit' and having its larger end of greater cross sectional area than the outlet end portion of said conduit, whereby air flowing along the outside of said conduit toward its gas discharge end is deflected into gases discharged from said conduit to dllutethem, and a plurality of sucessively smaller open-ended hollow flaring members spaced successively inwardly of one another and the larger or outermost of which has its smaller end joined to the smaller end of said hollow tapering member, thereby to provide a combined venturi and air diflusing structure to accelerate flow oi! diluted gases from the outlet end oi said conduit and to difl'use said gases.

3.In combination with an inflammable-gas conduit, an open-ended hollow tapering member disposed substantially in axial alinement with said conduit adjacent to the outlet end thereof and tapering in the direction of flow of gases discharged from said conduit and having its larger end of greater cross sectional area than the outlet end portion of said conduit, whereby air flowing along the outside of said conduit toward its gas discharge end is deflected into gases discharged from said conduit to dilute them, an open-ended hollow flaring member joined at its smaller end to the smaller end of said tapering member to provide a venturi structure to accelerate flow oi. diluted gases from the discharge end of said conduit, and means for diflusing the diluted gases comprising at least one other open-ended hollow let end portion of said conduit, whereby air flowing along the outside of said conduit toward its gas discharge end is deflected into gases discharged from said conduit to dilute them, an

open ended hollow flaring member joined at its smaller end to the'smaller end oi said tapering member to provide a venturi structure to accelerate flow of the diluted gases from the discharge end of said conduit, at least one other flaring member spaced inwardly from said flrst mentioned flaring member to eifect outward deflection and diffusion or the diluted gases, said second mentioned flaring member having a degree of flare diil'erent from the flare of said flrst mentioned flaring member, and at least one other open ended hollow tapering member spaced inwardly from said flrst mentioned tapering member and having a degree of taper diflerent from the taper of'said flrst mentioned tapering member to direct diluting air into the inflammable gases in a direction different from the direction or flow of the air directed into said gases bysaid flrst mentioned tapering member.

5. In combination with a conduit for gases of combustion, at least one open-ended hollow tapered member disposed substantially in axial alinement with said conduit adjacent to the outlet end thereof and tapering in the direction of flowof gases discharged from said conduit and having its larger end of greater cross sectional area than the outlet end portion of said conduit, whereby air flowing along the outside of said conduit toward its discharge end is deflected into gases discharged from said conduit to dilute them, and at least one open-ended hollow flaring member disposed substantially in axial alinement with said tapered member adjacent to the smaller or outlet end of the latter and flaring in the direction of flow of the gases and having its smaller end of smaller size than the smaller end of said tapered member to effect outward deflection and diffusion of the diluted gases.

6. The combination as set forth in claim 5 in which the smaller end of the tapered member is of greater cross "sectional area than the outlet end portion of the conduit to permit expansion of the gases as they issue from the conduit. 7 1

'7. In combination with a conduit for gases oi combustion, a plurality of successively larger open-ended hollow tapered members located ad- .lacent to the outlet end of said conduit and disposed substantially in axial alinement with one another and with said conduit and spaced axially in the direction of flow of the gases and tapering in the direction of flow of the gases issuing from the conduit, whereby air flowing along the conduit toward its discharge end is divided into separate streams and said streams are deflected inwardly into gases discharged from the conduit to dilute them, said memberssuccessivelyhaving greater amounts of taper to direct the successive diluting air streams more directly into the gases, and a plurality of successively smaller open-ended hollow flaring members disposed beyond the larger of said tapered members in axial alinement therewith and in the path of flow of the diluted gases to divide the same into separate flaring streams and to thus diffuse them.

8. The combination as set forth in claim 7 in which the smaller ends of the successively larger tapered members are successively larger and the smaller of which is of greater cross sectional area mable gas, means for supplying to ble as as it leaves the outlet end of said conduit a diluting non-inflammable gas sufllcient in quantity to render said inflammable gas non-inflam- 5 mable in the atmosphere immediately after leaving said conduit, and means beyond said first mentioned means for diil'using the diluted gas, said last named means comprising a plurality of successively smaller open-ended hollow flaring than the discharge end of the conduit to permit 10 members disposed in the path of now of the dithe gases to expand immediately upon issuing from the conduit.

9.'In combination with a conduit for inflamluted gas.

FRANZ J. KUR'IH. 

